Nonlinear optical materials with reduced aromaticity and bond length alternation

Abstract

Compositions for use in non-linear optical devices. The compositions have high first molecular electronic hyperpolarizability ( beta ) and therefore display high second order non-linear optical properties when incorporated into non-linear optical devices. The acceptor and donor groups which are used in the compositions, along with the pi (pi)-bridge length is chosen to optimize second-order non-linear optical responses.

What is claimed is: 
     
       1. A nonlinear optical device comprising: A) an element comprising a comprising a composition matter which exhibits a second-order nonlinear optical response, said composition having the formula: ##STR21## wherein C is ##STR22## wherein A is ##STR23## R is H, alkyl, aryl, (CH 2 ) x  OH where x=1 to 8, or (CH 2 ) x  SH where x=1 to 8; R' is H, alkyl, aryl, (CH 2 ) y'  OH where y'=1 to 8, or (CH 2 ) y'  SH where y'=1 to 8;     ML n  is a lewis acid;   wherein B is ##STR24## Y is CH═CH, O, NH, S or Se; D is OR", NR" R' or SR" where R" is H, alkyl, aryl or (CH 2 ) w  OH where w=1 to 8;   R" is H, alkyl, aryl or (CH 2 ) 2  OH where z=1 to 8;   or where R" R"' is derived from a cyclic amine of the form N(CH 2 ) 1  where I=3-10; and     wherein m is 0 to 15;   where the asterisk indicates the point of attachment on the acceptor and donor; and   B) means for directing at least one incident beam of electromagnetic radiation having at least one frequency into said element whereby electromagnetic radiation emerging from said element has at least one frequency which is different from said at least one frequency of said incident beam of electromagnetic radiation.   
     
     
       2. A nonlinear optical device according to claim 1 wherein said means for directing said incident beam of radiation is a laser. 
     
     
       3. A nonlinear optical device according to claim 1 wherein R is H or ethyl. 
     
     
       4. A nonlinear optical device according to claim 1 wherein R' is H or ethyl. 
     
     
       5. A nonlinear optical device according to claim 1 wherein R is H or ethyl. 
     
     
       6. A nonlinear optical device according to claim 1 wherein ML n  is (CH 3 ) 2  Zn, (CH 3 ) 3  A1, (CH 3 ) 3  Ga, (CH 3 ) 3  B Cl 3  Al, Cl 3  Ga, and Cl 3  B. 
     
     
       7. A nonlinear optical device according to claim 1 wherein said element comprises a thin film or a crystal.